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by Passiday
Tue Oct 27, 2020 7:25 pm
Forum: General discussion
Topic: Dealing with the system clock jump at startup
Replies: 14
Views: 606

Re: Dealing with the system clock jump at startup

DougieLawson wrote:
Tue Oct 27, 2020 1:55 pm
Do nothing more. You're good to go.
Thank you so much :)
But here's the last one - how to I detect in Python that the clock has been updated and will not jump anymore (well, except if daylight savings time changes, I guess)? Is there some file to wait, until it exists?
by Passiday
Tue Oct 27, 2020 10:39 am
Forum: General discussion
Topic: Dealing with the system clock jump at startup
Replies: 14
Views: 606

Re: Dealing with the system clock jump at startup

Did you also make the changes to /lib/udev/hwclock-set? No, but I just did that. What does that checking for /run/systemd/system do? systemd-timesyncd is an NTP service. It's just not the one we know and love. It looks like timedatectl has recognised the RTC - so all is good. Ok, but should I now d...
by Passiday
Mon Oct 26, 2020 10:44 pm
Forum: General discussion
Topic: Dealing with the system clock jump at startup
Replies: 14
Views: 606

Re: Dealing with the system clock jump at startup

Have you disabled the fake-hwclock stuff so that it doesn't interfere with the RTC? Ok, I have disabled it now. $ sudo systemctl status fake-hwclock.service ● fake-hwclock.service - Restore / save the current clock Loaded: loaded (/lib/systemd/system/fake-hwclock.service; disabled; vendor preset: e...
by Passiday
Mon Oct 26, 2020 5:00 pm
Forum: General discussion
Topic: Dealing with the system clock jump at startup
Replies: 14
Views: 606

Re: Dealing with the system clock jump at startup

In my case, there's a RTC available, on PiJuice, via I2C interface (dtoverlay=i2c-rtc,ds1339 in /boot/config.txt). But it is not available (ie, "sudo hwclock -r" doesn't return time) immediately at boot, so PiJuice support suggests first checking for PiJuice API readyness and only then move on with ...
by Passiday
Sat Oct 24, 2020 7:36 pm
Forum: General discussion
Topic: Dealing with the system clock jump at startup
Replies: 14
Views: 606

Dealing with the system clock jump at startup

I am running on my Pi Zero a project that has a server and client component. The client connects to the server, authenticates and receives a JWT token that contains the expiration time. This token then is used for all subsequent communitations with the server. Currently the token expiration time is ...
by Passiday
Fri Oct 23, 2020 5:05 pm
Forum: General discussion
Topic: Reliable power-off detection for Pi Zero
Replies: 15
Views: 553

Re: Reliable power-off detection for Pi Zero

Ok, well, I took a fresh SD card, burned the latest Raspbian image (2020-08-20-raspios-buster-armhf-lite.img), did the minimal config (keyboard, WiFi, SSH access), then added the "dtoverlay=gpio-poweroff,gpiopin=26,active_low=1" line to "/boot/config.txt" rebooted to activate the overlay, ...and eve...
by Passiday
Thu Oct 22, 2020 8:44 pm
Forum: General discussion
Topic: Reliable power-off detection for Pi Zero
Replies: 15
Views: 553

Re: Reliable power-off detection for Pi Zero

From what I remember there were additional hoops to be jumped through when driving a pin low. Don't remember the details so you'll ned to check /boot/overlauys/README Here's how my shutdown goes: https://youtu.be/iOtZpq3msn4 Shutdown starts at 0:03, Apparently it ends at 0:17 The GPIO26 pin remains...
by Passiday
Wed Oct 21, 2020 7:55 am
Forum: General discussion
Topic: Reliable power-off detection for Pi Zero
Replies: 15
Views: 553

Re: Reliable power-off detection for Pi Zero

It's not doing anything. AIUI the desired pin state should happen shortly after the clock save. The problem is that the pin state is HIGH all the time during that pause between the clock save and kernel panic. It falls to LOW only the moment when kernel panic happens. So, from the viewpoint of GPIO...
by Passiday
Tue Oct 20, 2020 9:05 pm
Forum: General discussion
Topic: Reliable power-off detection for Pi Zero
Replies: 15
Views: 553

Re: Reliable power-off detection for Pi Zero

Ok, in fact, I was a bit silly to assume by default that PiJuice uses the driving-GPIO3-low-to-boot method. That's just not true. I've set up the gpio-poweroff overlay on GPIO26 pin, and it seems to work - gives HIGH while the Pi Zero is running, and falls to ground about 1:45 after the shutdown com...
by Passiday
Tue Oct 20, 2020 7:46 pm
Forum: General discussion
Topic: Reliable power-off detection for Pi Zero
Replies: 15
Views: 553

Re: Reliable power-off detection for Pi Zero

You need to enable the UART/serial port but disable login and console output on it. Well I use the serial comms to communicate with Arduino. So it is enabled, and the login/console output is also disabled. As for the gpio-poweroff overlay disabling restart on GPIO 3, yeah that's what it odes as it ...
by Passiday
Tue Oct 20, 2020 6:28 am
Forum: General discussion
Topic: Reliable power-off detection for Pi Zero
Replies: 15
Views: 553

Reliable power-off detection for Pi Zero

I have a project that involves Pi Zero and several other devices connected to it: 10 RGB LEDs, I2S amp, an Arduino and few sensors. I use PiJuice with 12000 mAh battery to power it. All those devices draw some power when idle, so I want the PiJuice to cut power off when the Pi has shut down. And her...
by Passiday
Sun Aug 04, 2019 3:16 pm
Forum: General discussion
Topic: Powering my Pi Zero project
Replies: 4
Views: 278

Re: Powering my Pi Zero project

Have a look at the Pi - Juice Hat https://uk.pi-supply.com/products/pijuice-standard It may be a squeeze and cabling challenge depending on how other things are connected... In my project, there's not enough space to store the battery in HAT mode, so I have to use a product that has it's own pins a...
by Passiday
Sun Aug 04, 2019 3:11 pm
Forum: General discussion
Topic: Powering my Pi Zero project
Replies: 4
Views: 278

Re: Powering my Pi Zero project

How much current do you need to supply? I use Powerboost 1000c's on a few of my Pi builds but they have a 1 amp output limit. https://www.adafruit.com/product/2465 And there is this which is good for up to 2.5A https://www.dfrobot.com/index.php?route=product/search&search=MP2636 I am not entirely s...
by Passiday
Sat Aug 03, 2019 2:12 pm
Forum: General discussion
Topic: Powering my Pi Zero project
Replies: 4
Views: 278

Powering my Pi Zero project

I am close to finished with my project that features Pi Zero, 10 RGB LEDs, Arduino micro and DAC for a small 3W speaker. But I have trouble with the current power source — USB power bank. One thing is that it briefly cuts the output power when disconnected from the wall socket, but I managed to solv...
by Passiday
Thu Jan 10, 2019 6:37 pm
Forum: General discussion
Topic: Pi Zero W accessible via SSH only after long time
Replies: 7
Views: 604

Re: Pi Zero W accessible via SSH only after long time

Thank you all for suggestions. The messages from the startup what I mentioned in my post were hand-written from the display connected to HDMI. So I have no problem seeing what's going on, at least if that is reflected in the HDMI output. What I failed to mention is that I have Arduino Micro connecte...
by Passiday
Tue Jan 08, 2019 4:38 pm
Forum: General discussion
Topic: Pi Zero W accessible via SSH only after long time
Replies: 7
Views: 604

Pi Zero W accessible via SSH only after long time

I have set up my router to assign IP(v4) fixed address to the Pi Zero W. IPv6 is disabled on router. I have loaded Raspbian Stretch Lite on the SD card. When I power it up, among the last on-screen messages, among those are: [ OK ] Reached target Network ...(some more lines) My IP address is 192.168...
by Passiday
Mon Dec 17, 2018 12:04 pm
Forum: Graphics, sound and multimedia
Topic: I2S DAC, alsamixer: device does not have any controls
Replies: 5
Views: 8131

Re: I2S DAC, alsamixer: device does not have any controls

Hello, My project is a media player, hidden in a kids toy (pimped-up vintage dial phone). I have set up my Pi Zero with MAX98357A amp, and used the asound.conf example from this thread to get the software volume control. I have installed vlc-nox package that includes vlc headless player, to play mp3...
by Passiday
Fri Jul 10, 2015 8:11 pm
Forum: Advanced users
Topic: How to look for an appropriate screen?
Replies: 3
Views: 823

Re: How to look for an appropriate screen?

Ok, so I picked this one: http://www.amazon.co.uk/Screen-Raspberry-Controller-6-5inch-AT065TN14-6-5-Inch-800-X-480/dp/B00YIIXP34 @RaTTuS, you are completely correct on all those other concerns, ie battery, etc. There's also place for infrared sensor, and controller for the motor that drives the disp...
by Passiday
Thu Jul 09, 2015 2:43 pm
Forum: Advanced users
Topic: How to look for an appropriate screen?
Replies: 3
Views: 823

How to look for an appropriate screen?

I am planning to replace the lousy PC that sits in my car's navigation computer bay ( looking like this ) with RasPi 2. But I plan to keep the existing casing, because it contains cool mechanics that raise and lower the display from the car's front panel. So I have pulled out the casing, stripped it...
by Passiday
Mon Jun 10, 2013 11:56 am
Forum: Python
Topic: CEC reading
Replies: 3
Views: 901

Re: CEC reading

No, not really. But then again, I wasn't trying too hard.
by Passiday
Mon Jan 07, 2013 8:03 am
Forum: Troubleshooting
Topic: USB wireless keyboard not active after boot
Replies: 3
Views: 965

Re: USB wireless keyboard not active after boot

It's Logitech K400: http://www.logitech.com/en-us/product/w ... board-k400
It doesn't seem to drop keys but only this startup recognition problem. The result of lsusb command is exactly the same when the dongle is pulled out and plugged back again.
by Passiday
Mon Jan 07, 2013 6:34 am
Forum: Troubleshooting
Topic: USB wireless keyboard not active after boot
Replies: 3
Views: 965

USB wireless keyboard not active after boot

I have wireless keyboard/trackpad USB dongle attached to my Pi, and after reboot it doesn't seem to receive signals from the keyboard (rarely, but sometimes it works tho). If I ssh to the Pi and do lsusb, then I see the respective Logitech device in the list. If I'd now remove the USB dongle and plu...
by Passiday
Fri Dec 28, 2012 2:00 pm
Forum: Media centres
Topic: Boot to Wheezy by default, keep XBMC as application
Replies: 0
Views: 803

Boot to Wheezy by default, keep XBMC as application

Hello, I followed instructions from http://elinux.org/RPi_XBMC to install the XBMC on Wheezy, because I wanted to keep using my Pi (Model B, with 512Mb RAM) for other projects in Wheezy. So, OpenELEC is not an option in my case. But I experience several problems in this setup, I hope they are easy t...
by Passiday
Wed Dec 26, 2012 7:48 pm
Forum: Python
Topic: CEC reading
Replies: 3
Views: 901

CEC reading

Hello,

I am looking for a way how to listen to CEC signals (the one over HDMI) in Python app?

Perhaps the "right way" is to install libCEC and wrap it for Python access, but I have too little knowledge to do it on my own.

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